#21903: Query with select_related and defer on MySQL causes id field to be
returned
as bool
-------------------------------------+-------------------------------------
Reporter: matklad | Owner: nobody
Type: Bug | Status: new
Component: Database layer | Version: 1.6
(models, ORM) | Resolution:
Severity: Normal | Triage Stage: Ready for
Keywords: | checkin
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
Changes (by akaariai):
* component: Uncategorized => Database layer (models, ORM)
* stage: Unreviewed => Ready for checkin
Comment:
Seems like patch 9918c11114ac3ec9622631558ef26ebf3919cb69 (#21413) should
be backpatched from master. I don't recall why I didn't do that
originally, maybe I just forgot to do that.
See
https://github.com/akaariai/django/compare/django:stable%2F1.6.x...ticket_21903_16
for a branch having tests for this ticket + backpatch of #21413. I think
that there isn't point in adding this ticket's tests. The backpatch has a
much simpler test case. I'll mark this RFC, but I'll wait a little bit for
possible reviewers.
As for why these bugs happen - the compiler.resolve_columns() is trying to
mimic what SELECT clause generation is doing. And, unfortunately the
SELECT clause generation is complex (caused by defer, select_related,
annotations and extra). In the long term we should probably move to
something where select setup generates a list of "col_sql, alias, field",
and then resolve_columns could just use that list.
--
Ticket URL: <https://code.djangoproject.com/ticket/21903#comment:3>
Django <https://code.djangoproject.com/>
The Web framework for perfectionists with deadlines.
--
You received this message because you are subscribed to the Google Groups
"Django updates" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
To post to this group, send email to [email protected].
To view this discussion on the web visit
https://groups.google.com/d/msgid/django-updates/065.63369ae35462749c194e35978c21f7ad%40djangoproject.com.
For more options, visit https://groups.google.com/groups/opt_out.
